1. Field of the Invention
The present invention relates to a disc cartridge having encased therein a disc-shaped recording medium such as an optical disc, magneto-optical disc or the like.
2. Description of the Related Art
As the disc-shaped recording medium, a disc cartridge having a magneto-optical disc for example encased therein has been proposed.
Referring now to FIG. 1, there is schematically illustrated a conventional disc cartridge in the form of a perspective view. In FIG. 1, the disc cartridge is generally indicated with a reference 201. The disc cartridge 201 includes a cartridge body 206 consisting of a pair of upper shell 211 and lower shell 212 assembled to each other. These upper and lower shells 211 and 212 are made of a resin material. Each of the upper and lower shells 211 and 212 has formed therein an access opening 215 having a generally rectangular shape. The access openings 215 are opposite to each other. Thus, a part of the recording area of the magneto-optical disc 205, extending between lead-in and lead-out areas, is exposed outside through the openings 215 for data read and write.
The lower shell 212 of the cartridge body 206 has formed therein adjacent or next to the access opening 215 and a drive opening 217 through which a disc table (not shown) of a disc drive mechanism which drives to rotate the magneto-optical disc 205 comes into the cartridge body 206.
Further, the cartridge body 206 has a shutter member 220 mounted thereon as shown in FIG. 1. Normally, the shutter member 220 covers or closes the access openings 215 and drive opening 217. When the disc cartridge 201 is loaded into a recorder/player, the shutter member 220 will be moved and thus the access and drive openings 215 and 217 will be opened. The shutter member 220 consists of an upper shutter portion which closes and opens the access opening 215 in the upper shell 211, a lower shutter portion which closes and opens the access openings 215 and drive opening 217 in the lower shell 212, and a connection to which each of the upper and lower shutter portions is connected at one end thereof.
When the disc cartridge 201 constructed as in the above is loaded into the recorder/player, the shutter member 220 is moved by a shutter open/close member of the recorder/player to open the access openings 215 and drive opening 217. The disc table of the disc drive mechanism (not shown) of the recorder/player comes into the disc cartridge through the drive opening 217 to rotate the magneto-optical disc 205 in the disc cartridge 201, while the write/read head of the recorder/player comes into the disc cartridge 201 through the access openings 215 to write/read information to/from the magneto-optical disc 205.
In the aforementioned conventional disc cartridge 101, however, since the front end thereof at which the disc cartridge 201 is first inserted into and removed from the recorder/player is formed straight perpendicularly to the direction of insertion into the recorder/player and both the main sides of the cartridge body 206 are formed generally square, it is difficult to easily know the correct inserting direction of the disc cartridge 201 from its appearance.
Therefore, the conventional disc cartridge 201 is likely to be inserted in a wrong direction into the recorder/player.
In the conventional disc cartridge 201, the width of the access openings 215 should desirably be larger for accommodating any write/read head of the recorder/player which will vary from one type of the recorder/player to another. However, if the width of the access openings 215 in the disc cartridge 201 is thus made larger, the upper and lower shutter portions of the shutter member 220 will be larger and the shutter member 220 is moved over a longer distance, which will disadvantageously result in a larger size of the cartridge body 206 or in protrusion of the shutter member 220 to outside the cartridge body 206 when the access openings 215 are opened. Therefore, in the conventional disc cartridge 201, the access openings 215 cannot be designed large.
It is therefore an object of the present invention to overcome the above-mentioned drawbacks of the prior art by providing a disc cartridge having a body whose front end to be opposite to a recorder/player may be designed to have an arbitrary shape for easy knowing of a correct direction of insertion into the recorder/player and provided with a shutter open/close mechanism assuring a large width of an access opening for write and/or read to and/or from a disc encased in the disc cartridge.
The above object can be attained by providing a disc cartridge including according to the present invention a disc-shaped recording medium; a cartridge body having formed therein a disc compartment to house the disc-shaped recording medium; an access opening formed in the cartridge body and through which a part of the recording area of the disc-shaped recording medium, extending between lead-in and lead-out areas, is exposed outside for data read and write; a pair of shutter members provided movably towards and away from each other to open and close the access opening; and a shutter open/close mechanism having a pair of guide recesses formed in a main side the of the cartridge body to be oblique in relation to the width of the cartridge body to support the pair of shutter members, respectively, to be movable.
In the disc cartridge constructed as in the above, the pair of shutter members is moved towards and away from each other along the pair of guide recesses formed in the main side of the cartridge body to be oblique relative to the width of the cartridge body ti open and close the access opening. Therefore, in this disc cartridge, since the pair of shutter members is moved towards and away from each other in relation to the access opening, it is possible to assure a large width of the access opening.
In the above disc cartridge according to the present invention, the guide recess formed on a main side of the cartridge body to be oblique relative to the width of the cartridge body allows the front end of the cartridge body at which the disc cartridge is first inserted into the recorder/player to be formed in an arbitrary shape for easily knowing a correct direction of insertion in the recorder/player, so that the disc cartridge can be prevented from being inserted in a wrong direction into the recorder/player. Also, in this disc cartridge, the pair of shutter members provided allows to design a large width of the access opening and also can be moved positively relative to the access opening.
These objects and other objects, features and advantages of the present intention will become more apparent from the following detailed description of the preferred embodiments of the present invention when taken in conjunction with the accompanying drawings.